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Paddy Soil Characteristics Influence Rice Production

Conceivably no major food crop other than wheat can compete with rice in the range of climatic and hydrologic conditions under which, it is grown. Rice is produced in every continent except antarctica and thrives in an area ranging in latitude from 55° to 40°. It grows as a dryland crop much like wheat or maize, as a rain fed crop under alternately submerge and dry condiiions. and as a continuously flooded crop. Farmers grow rice on alluvial plains. Hooded valleys, and terraced hillsides. Even though it has less drought tolerance than other cereals, rice grows well in arid areas under irrigation such as in Asia and north Africa. Likewise, despite riceʹs sensitivity to low temperature, yields are high in northern Japan and China and at elevations of more than 3.(){){) meters above sea level in ihe tropics and sublropics. Most paddy soils are located at lower posiiions in landscapes to permit water easy access from higher irrigation or natural surface runoff sources. These wetland rice areas may be flat-bottomed \ alleys or terraced and bounded hillsides of otherwise upland areas. But more often, they are found in alluvial flood plains, deltaic plains, coastal plains, tidal flats, marshes, and major river valleys. Such areas are generally characterized by a natural or induced "aquie" moisture regime that implies high moisture and low oxygen condiiions. As a consequence of this high moisture-low oxygen requirement, the soil characteristics for paddy rice culture may vary less than those for upland or dryland rice